Figures, I must of caught some of Farmerbeau's bad luck when I helped him on his truck. Swapped in the GT2-3 and ls6 springs last weekend, no issues til last night. Cruising at highway speed ~70-75, check engine light comes on. I don't hear for feel much til I exit the highway. Truck dies and won't run, unless gassed pretty good. I had to get towed home.

Under the valve covers was a surprise today. Cylinder 1 exaust side lifter stuck with the valve open. Intake valve spring broken on the same cylinder, and this valve seems to bind to the seat a little. Cylinder 2 exhaust side lifter stuck like the other side. No loose rockers at all.

I am not sure what caused this, and I am open to suggestions especially the ones where I f$$cked something up. The swap itself went smoothly and the truck ran great all week until last night. Never a drop in oil pressure. I changed the oil and no coolant in it or any significant amount of metal on the drain plug. I pulled the spark plugs and nothing remarkable there. I have been running on the tune Charlie did for the stock cam. No engine light since intall, until last night.

There is a severe limitation on time since I have plans to pull a medium size Uhaul trailer for moving purposes to North Carolina in less than 2 weeks.

As of right now I need to have this thing up and running quickly and I guess will have it towed to a shop. I am thinking MTI or HPE (if they still exist) might be able to rip off the heads and check 'em for damage, fix 'em up or replace 'em, put new lifters in, and possibly a new valve or two if needed. I would get parts and try and fix tis myself with some help, but my main problem is time, I just don't have it right now.

Any thoughts 'bout what went wrong, shops, or otherwise appreciated.

 

im assuming you did a cam and lifters? a friend of mine just built a 383, new everything and within 30 miles had 9 collapsed lifters, maybe you just got some bad lifters. you said the valves feel like they are binding up a little, maybe you somehow bent the valves (like not resetting the timing for the bigger cam, or not degreed correctly)

 

pm silver-mod-o, i think he is near you and might be able to diagnose it for you

 

thanks, I did not swap lifters, just cam and springs. I guess it is possible I bent some when installing the springs, but I kinda doubt it. I used the crane spring compressor with out any trouble. But I did use the TDC method to keep the valves from falling.....no binding on install on the affected valves or springs.

 

i wasnt talking about bending them during installation, pistons hitting valves is what i was referring to

 

Did you not change the pushrods?

 

What are the specs on that cam?

 

New or used springs? What springs??

 

ls6 springs.

 

bad news first.
the cam has a lift of 578, the LS6 springs are only good to 570 and thats pushing it.
your stock pushrods were way too long, if thier not bent i would bet on a few lifters being damaged as well.

if your pistons are fine you are going to need a new set of heads, or a good used set.
if you do not have a set of 7.4 pushrods to work with the G2-3 cam you will need a good stock set while you place the stock cam back in.

tomorrow is clumbus day, postoffice and banks are closed, so will a few other places that see it as a holiday to take off.

right now make a parts list of what you need.
i did my head gaskets in one day all by my self so i know it can be done with the help of a friend.